Billionaire tech entrepreneur, investor and Dallas Mavericks owner Mark Cuban spoke at South by Southwest on Saturday. He told the audience that the greatest life lesson he's learned came from his father.

It's to have fun at every age.

"My dad is 87. He’s going strong, he's a machine," Cuban said. "My dad says it over and over, 'Today’s the youngest you’re ever going to be. You’ve got to live like it. You've got to live young every day.' And that’s what I try to do."

When asked what other lessons he learned from his parents, Cuban recited the golden rule.

"I learned how to treat people. Treat people with a level of respect. You don’t think you’re anything special," he said. "There are plenty of times I’m arrogant but I always try to treat people the way I’d want to be treated and never think, I’m better than you. Because your bank account doesn’t define you — at least mine doesn't define me."